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1

Seismic attribute analysis of Chicxulub impact crater

Salguero-Hernández E., Pérez-Cruz L., Urrutia-Fucugauch i J.

Acta Geophysica

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2020

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Vol. 68, no. 3

627--640

EN

Chicxulub crater formed~66 Ma ago by an asteroid impact on the Yucatan platform in the southern Gulf of Mexico. The crater has a ~ 200 km rim diameter and has been covered by carbonate sediments up to ~ 1.1 km thick in the central zone. Previous studies have identifed the structure and major crater units through geophysical models from seismic refection and potential feld data, classifed as the central uplift, terrace zone, outer and inner ring fault zones and impactite deposits. Impact produced a deep excavation cavity, with fragmentation and ejection of large volumes of crustal target rocks. Understanding the pre-existing structures, impact-induced deformation and post-impact processes requires high-resolution images of the crater and target zone. For this study, we use complex trace attributes of instantaneous phase, frequency, envelope amplitude and similarity, in an E-W seismic refection profle crossing the crater in the marine sector. Geophysical logs and borehole lithological columns from the on-land drilling projects are used to constrain the petrophysical analysis. Seismic attributes aid to characterize the radial fault zones and physical property contrasts, revealing asymmetries in the crater structure. The refector packages in the post-impact sediments and target Cretaceous sequence are identifed in the frequency and phase attributes. The bottom crater refectors, with the basal sediments flling the crater foor topography, are enhanced with the envelope amplitude attribute. A set of high-amplitude refectors is shown in the similarity attribute, in which the refector geometry is delineated on the target carbonate sequence. The ofsets in the high-amplitude refectors between the eastern and western sectors are possibly associated to target pre-impact asymmetries, impact deformation and efects of central crater collapse.

2

Mineralogia drobnoziarnistych utworów z krateru meteorytu Morasko

Duczmal-Czernikiewicz A., Muszyński A

Biuletyn Państwowego Instytutu Geologicznego

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2015

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nr 464

17--23

PL

Przedstawiono wstępne wyniki badań mineralogicznych utworów w rejonie rezerwatu przyrody Meteoryt Morasko znajdującego się w północnej części Poznania. Ponad 5000 lat temu spadł tu meteoryt, a ślad tego zdarzenia zaznacza się w morfologii w postaci kilku zagłębień oraz otaczających je wałów. Rejon rezerwatu jest zbudowany z glin polodowcowych i podścielających je iłów formacji poznańskiej. Prace wykonano w celu rozpoznania składu mineralnego utworów, ustalenia potencjalnych mineralogicznych skutków uderzenia meteorytu oraz określenia, jak wpłynęło ono na miękkie, młode osady. Metodami mikroskopowymi i rentgenowskimi oznaczono podstawowe składniki glin i iłów, zbadano frakcje ziarnowe glin oraz wyróżniono ich składniki pierwotne i wtórne. Do składników pierwotnych należą: kwarc, skalenie, pirokseny, minerały ilaste (illit, kaolinit), a także otoczaki skał magmowych. Procesy wietrzenia doprowadziły do powstania składników wtórnych: współczesnych gleb (humus, fragmenty korzeni) oraz glinokrzemianów z grupy wermikulitu. Materiał wtórny stanowią także klasty ilastych skał starszego podłoża, zawierających składniki typowe dla formacji poznańskiej (illit, kaolinit, smektyt i minerał mieszanopakietowy smektyt/ illit, bardzo drobnoziarnisty kwarc oraz prawdopodobnie skalenie). Na podstawie wyników dotychczasowych obserwacji i badań stwierdzono, że obecność klastów ilastych w glinach może być związana z upadkiem meteorytu.

EN

The present paper shows preliminary results of mineralogical studies of sediments in the Morasko Meteorite Nature Reserve located in the northern part of Poznań. The meteorite fell there over 5000 years ago, that left signs in the present morphology of the region in form of several craters and elevations that surround them. These forms are underlain by glacial tills and clay – silt sediments, known as the Poznań Formation. The aim of the research was to identify of the mineralogical composition of sediments, determine potential mineralogical effects of the meteorite fall, verify the impact of the meteorite fall on soft young sediments. The studies were conducted with the use of microscopic and X-ray diffraction equipment. Primary and secondary components were identified in grain fractions. Quartz, feldspar, pyroxene, clay minerals (illite, kaolinite), and pebbles of igneous rocks are the primary components of the sediment. Weathering processes resulted in the development of modern soil profiles (humus, root fragments) and aluminum silicates of vermiculite-type minerals. The secondary components are clay clasts of older rocks in younger ones, which contain components typical of the Poznań Formation (illite, kaolinite, smectite or mixed-layered smectite/ illite, very fine-grained quartz and likely feldspars). The presence of clay intercalations in tills can be associated with the meteorite fall.

3

Charakterystyka petrograficzna skał pochodzących ze struktury impaktowej Gardnos, Norwegia

Jarmołowicz-Szulc K., Ilcewicz-Stefaniuk D., Stefaniuk M.

Biuletyn Państwowego Instytutu Geologicznego

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2015

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nr 464

43--48

PL

Krater meteorytu Gardnos znajduje się w Norwegii, ok. 125 km na północny zachód od Oslo. Cała struktura jest dobrze widoczna w terenie dzięki licznym odkrywkom brekcji impaktowych i utworów poimpaktowych występujących w okręgu o promieniu ok. 5 km. Główne typy skał impaktowych w rejonie krateru Gardnos to autochtoniczna brekcja z Gardnos oraz przykrywająca ją allochtoniczna brekcja impaktowa (suevit). W artykule omówiono petrografię tych skał. Brekcja z Gardnos jest brekcją lityczną, złożoną ze spękanych fragmentów skał, ale nie zawiera fragmentów stopu. Suevit jest brekcją polimiktyczną, zawierającą małe fragmenty zrekrystalizowanego stopu z klastami skał i minerałów.

EN

The crater of the Gardnos meteorite is located in Norway, about 125 km north-west of Oslo. The structure is well seen due to the outcrops of impact breccias and post-impact deposits that form a circle with a radius of about 5 km. Main types of the impact rocks in the Gardnos area are the autochthonous Gardnos breccia and its cover – allochthonous suevite breccia. The petrological characteristics of these rocks are presented. The Gardnos breccia is a lithic breccia, composed of fissured rock fragments, without melt components. The suevite is a polymictic breccia, built of small fragments composed of recrystallized melt and clasts of rocks and minerals.

4

Energetyczna weryfikacja i symulacja efektów ostrzału

Zatorski Z., Flis L.

Logistyka

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2014

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nr 5

1725-1733

PL

W prezentowanej pracy wskazano na możliwość rozwiązania problemu tworzenia krateru przy ostrzale tarczy z wysokimi prędkościami w ramach hydrodynamicznej teorii ośrodka ciągłego i użycia modeli fenomenologicznych. Podczas analizy wykorzystano gęstość i twardość materiałów pocisku i tarczy jako istotne parametry tych modeli. W prezentowanej pracy, pokazano ograniczoność tych modeli w zakresie geometrii tarczy i pocisku oraz prędkości ostrzału, wykorzystując energetyczną weryfikację i symulację komputerową efektów ostrzału. Energię właściwą tworzenia krateru porównano z absorbowaną przez materiał energią właściwą odkształceń plastycznych, uzyskaną z pomiarów twardości Brinella.

EN

In presented work, behavior of the metals plate are impacted by projectiles at high velocity impact is developed. Proper impact energy of crater creation is energetic veri fied with Brinell hardness of constructional materials. Brinell hardn ess is compared with proper ene rgy of plastic strain absorbed in material. The experimental tests were carried out at materials testing systems FU 1000 and MTS 810.12 at the Polish Naval Academy in Gdynia. An analysis of load–penetration curves from inst rumented indentation is used to designation of elastic, plastic and total strain energy absorbed in materials. Together, the impact effect and Brinell hardness are energetic verified.

5

The first Polish tektites: preliminary SEM investigation

Brachaniec T., Szopa K., Karwowski Ł.

Contemporary Trends in Geoscience

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2013

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Vol. 2, iss. 1

18--21

EN

In Lower Silesia, the first Polish moldavites were discovered. To recognize the primary chemical composition and check the morphology of investigated material SE and BSE images were used. The samples show presence of vesicles, which are one of the most typical features of tektite glass. Referring to the preliminary EDS results and comparing them with literature data, it can be assumed that in all cases the base material for all known moldavites was the same.

6

Morphology of traces made by individual electric discharge in the EDM

Nowicki B., Dmowska A., Podolak-Lejtas A.

Advances in Manufacturing Science and Technology

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2009

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Vol. 33, nr 4

5-24

EN

The paper deals with a new method of investigating traces made by individual discharge using SEM and scanning profilometers. Surface microstructure is assessed using the SEM while dimensions and volumes of individual craters are determined basing on scanning profilometer SP. The influence of machining conditions on micro-structure of trace surface, crater and flash dimension and volume were investigated. It was concluded that discharge traces after the EDM (Electro-Discharge Machining) are typical of strong connection with machining parameters and they are highly repeatable whereas discharge traces generated on the cathode surface during the EDA (Electro Discharge Alloying) are much larger than those after the EDM and they are typical of much less uniform size and volume.

PL

W pracy przedstawiono charakterystykę śladów pojedynczych wyładowań generowanych podczas obróbki EDM i EDA. Prowadzono badania za pomocą mikroskopu skaningowego (SEM) i profilometru skaningowego. Powierzchnię śladów wyładowań obserwowano za pomocą mikroskopu SEM, natomiast rozmiary i objętość kraterów określono, stosując profilometr skaningowy. Ustalono wpływ parametrów obróbki na mikrogeometrię powierzchni, a także rozmiary oraz objętość kraterów i wypływek. Stwierdzono, że rozmiary śladów wyładowań po EDM są ściśle skorelowane z parametrami obróbki i charakteryzują się dużą powtarzalnością. Ślady wyładowań generowanych podczas stopowania elektroiskrowego (EDA) mają natomiast większe rozmiary w porównaniu z obróbką EDM. Charakteryzuje je również duża przypadkowość.

7

Plasma jet generation by flyer disk collision with massive target

Kasperczuk A., Pisarczyk T., Borodziuk S., Gus'kov S. Y., Ullschmied J., Krousky E., Masek K., Pfeifer M., Rohlena K., Skala J., Kalal M., Limpouch J., Pisarczyk P.

Optica Applicata

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2007

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Vol. 37, nr 1-2

73-82

EN

In this paper, results from experiments with Al flyer targets (disks with a diameter of 300 mm and a thickness of 6 mm) accelerated at first to high velocities by PALS iodine laser pulses (with an energy of 130 J, pulse duration of 400 ps, a wavelength of 1.315 mm, and laser spot diameter of 250 mm), subsequently creating craters after their collisions with massive Al targets (placed at a distance of the order of 200 mm) are presented. To measure the plasma density evolution a three frame interferometric system was employed. The experimental results demonstrate that the flyer disk-massive target collision generates an axial plasma jet corresponding to a flat shock wave propagating in a massive target. This form of the shock wave was deduced from a crater trapezoidal shape which was reconstructed by means of crater replica technique.

8

New data on the post-impact material in radiolarian horizons in Outer Flysh Carpathians and search for a source crater

Paul Z., Halas S., Wójtowicz A.

Geochronometria

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2007

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Vol. 27

17-22

EN

In the Outer Carpathians in Barnasiówka radiolarian shale formation, there is an intercalation underlied by bentonite. There were found very rare elements and minerals in this intercalation. It was recognized that this horizon has been filled with products of a big object collision with Earth. The age of the manganese-iron intercalation was determined by potassium-argon (K-Ar) dating of illites to be (89.3±1.2) Ma. Similar age, (85.2±0.6) Ma, was found for the post-impact glass from the Boltysh crater in Ukraine. It was concluded that the formation of this intercalation was synchronous with the Boltysh crater formation at the Cenomanian/Turonian boundary. The research for the K-Ar age of the crater creation in Logoisk (Belarus) established its formation to (124.2±1.2) Ma ago.

9

High power laser interaction with single and double layer targets

Borodziuk S., Demchenko N. N., Guskov S. Y., Jungwirth K., Kalal M., Kasperczuk A., Kondrashov V. N., Kralikova B., Krousky E., Limpouch J., Masek K., Pisarczyk P., Pisarczyk T., Pfeifer M., Rohlena K., Rozanov V.B., Skala J., Ullschmied J.

Optica Applicata

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2005

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Vol. 35, nr 2

241-262

EN

Results of extended complementary experimental and computer simulation studies of craters formation produced by high power lasers in single and double layer targets are presented. The experimental investigation was carried out using the PALS (Prague Asterix Laser System) facility working with two different laser beam wavelengths: L(lambda)1 = 1.315 žm and L3 = 0.438 žm. Two types of targets made of Al were used: single massive targets and double targets consisting of foils or disks (6 and 11 žm thick for both cases) placed in front of the massive target at distances of 200 and 500 žm. The targets were illuminated by laser energies EL= 130, 240 and 390 J always focused with diameter of 250 žm. In all experiments performed the laser pulse duration was equal to 400 ps. The 3-frame interferometry was employed to investigate the plasma dynamics by means of the electron density distribution time development, as well as the disks and foil fragments velocity measurements. Dimensions and shapes of craters were obtained by crater replica technology and microscopy measurement. Experimental results were complemented by analytical theory and computer simulations to help their interpretation. This way the values of laser energy absorption coefficient, ablation loading efficiency and efficiency of energy transfer, as well as 2-D shock wave generation at the laser-driven macroparticle impact, were obtained from measured craters parameters for both wavelengths of laser radiation. Computer simulations allowed us to obtain an energy absorption balance of incident laser energy for both wavelengths employed.

10

Investigation of plasma ablation and crater formation processes in the Prague Asterix Laser System laser facility

Borodziuk S., Kasperczuk A., Pisarczyk T., Gus'kov S., Ullschmied J., Kralikova B., Rohlena K., Skala J., Kalal M., Pisarczyk P.

Optica Applicata

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2004

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Vol. 34, nr 1

31-42

EN

The present investigation of the processes of ablative plasma generation and formation of craters was carried out at the Prague Asterix Laser System (PALS) iodine laser facility. Experiments were performed with broad range of laser beam intensities (1013-1016 W/cm2), focal spot radii (35–600 mm), and two laser wavelengths (l1 = 1.315 mm and l3 = 0.438 mm). The laser beam was focused on the surface of the massive solid aluminum targets. The main goal of our study was to estimate conversion efficiency of the laser beam energy into the energy of shock waves for different mechanisms of laser beam–target interaction. The expansion of plasma generated as a result of the interaction process was observed by means of the 3-frame interferometry. Dimensions and shapes of the craters were determined using optical microscopy and wax-replica technique.

11

Application of the 3-frame interferometry and the crater replica method for investigation of laser accelerated macroparticles interacting with massive targets in the Prague Asterix Laser System (PALS) experiment

Borodziuk S., Kasperczuk A., Pisarczyk T., Demchenko N.N., Gus’kov S., Rozanov V. B., Kalal M., Limpouch J., Ullschmied J., Rohlena K., Skala J., Kondrashov V. N., Pisarczyk P.

Optica Applicata

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2004

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Vol. 34, nr 3

385-403

EN

In the present paper results from our experiments with macroparticles, accelerated at first to high speeds by the PALS iodine laser and subsequently hitting massive targets and creating craters, are presented. The main aim of these investigations concerned the influence of wavelength on the efficiency of macroparticles acceleration and creation of craters. To this end, two different harmonics of the PALS laser beam (l1 = 1.315 mm and l3 = 0.438 mm) and several types of targets (simple massive planar Al targets as well as much more elaborated double targets consisting of 6 mm thick Al foils or disks placed in front of the massive target at the distance of either 200 mm or 500 mm) were used. All these targets were irradiated by the iodine laser beam with its parameters very much the same for both harmonics: the energy of 130 J, the focal spot diameter of 250 mm, and the pulse duration of 400 ps. Velocities of accelerated extracted foil fragments or disks as well as electron density distributions of plasma streams were determined by means of the 3-frame interferometry. Shapes and volumes of craters were obtained employing the crater acetate cellulose replica technology and microscopy measurements. The data from these experiments provided valuable information concerning the ablative plasma generation and crater creation processes.

12

Experimental and theoretical investigations of crater formation in an aluminium target in a PALS experiment

Borodziuk S., Doskach I., Gus'kov S., Jungwirth K., Kálal M., Kasperczuk A., Kralikova B., Krousky E., Limpouch J., Masek K., Pfeifer M., Pisarczyk P., Pisarczyk T., Rohlena K., Rozanov V., Skala J., Ullschmied J.

Nukleonika

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2004

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Vol. 49, nr 1

7-14

EN

Experimental and theoretical results of investigations of the iodine laser - Al solid target interactions on the PALS (Prague Asterix Laser System) facility are presented. The experimental investigations of laser interaction with massive Al targets devoted to shock wave propagation in solids and crater formation physics are presented. Experiments were performed with the use of high intensity laser pulses (1013 15 W/cm2) for two laser wavelengths (0.438 mi m and 1.315 mi m) and four laser beam radii (from 35 mi m up to 600 ěm). The crater dimensions were measured using optical microscopy and a wax-replica technique. Plasma expansion out of the target was measured via three-frame interferometry. Theoretical model of the postpulse crater formation by the shock wave propagating and decaying in solids after the end of the laser pulse is presented and applied for the explanation of the results obtained in experiments.